PM2.5质量浓度廓线的激光雷达反演研究

针对PM2.5质量浓度在空间不同高度上的分布测量较难这一问题,采用激光雷达和大气透射仪以及粒径谱仪进行联合探测,反演PM2.5质量浓度廓线.考虑相对湿度等因素的影响,通过大气透射仪和粒径谱仪建立地面PM2.5质量浓度与大气透过率之间的函数关系.以大气透射仪所测地面大气透过率值为基准,修正激光雷达大气透过率在高空的边界值,结合Fernald后向积分法反演出大气透过率的垂直分布.依据建立的函数关系和大气透过率垂直分布,得到PM2.5质量浓度廓线,并采用HYSPLIT后向轨迹分析不同高度层气溶胶的输送和动态变化.通过激光雷达、大气透射仪和粒径谱仪的联合探测实验,结果表明:经大气透射仪修正后,大气透过率垂直分布精度得到了提高,PM2.5质量浓度廓线很好的反映了气溶胶垂直分布的微物理变化特征.

Lidar Inversion of PM2.5 Mass Concentration Vertical Distribution

PM2.5 concentration distribution measurement in space at different heights is difficult,this paper uses lidar and atmospheric transmission meter and particle spectrometer for joint detection,through three kinds of instrument data with the vertical distribution of PM2.5 concentration inversion.The function relationship between mass concentration of ground PM2.5 and atmospheric transmissivity is established by data of atmospheric transmittance and particle size spectrometer.Based on the ground atmospheric transmittance measured by the atmospheric transmission meter,the boundary value of the lidar atmospheric transmittance at high altitude is determined through an iterative algorithm,and the vertical distribution of the atmospheric transmittance is retrieved in combination with Fernald integral method.The vertical distribution of PM2.5 mass concentration is obtained by the atmospheric transmittance height profile detected by lidar.The results showed that the accuracy of the vertical distribution of atmospheric transmittance has been improved by the revised atmospheric transmittance.The profile of PM2.5 mass concentration well reflects the microphysical variation of the vertical distribution of aerosols.